Purdue is the main manifestation of ghost worship, which should be said to be a folk custom. "Purdue" was originally a Buddhist term, meaning the extensive application of Buddhism and the liberation of all beings. As early as before the Han Dynasty, there were three festivals in China: Shangyuan Festival, Zhongyuan Festival and Xiayuan Festival. July 15 is the Mid-Autumn Festival, which is a festival to worship ancestors. At the end of the Western Han Dynasty and the beginning of the Eastern Han Dynasty, Buddhism was introduced to China, which developed rapidly during the Wei, Jin, Southern and Northern Dynasties, and the story of "Mu Lian saved the mother" in Buddhism spread. Because the legend of Manglietia Manglietia Saving Mother coincides with China's traditional spirit of filial piety and ancestor worship, it was quickly accepted by people. The Buddhist Bonsai Society, which was initiated by Liang Wudi in the Southern Dynasties and centered on the story of Mulian saving his mother, was gradually replaced by the Mid-Yuan Festival. The Qianlong edition of Quanzhou Fuzhi contains: "Worship comes first in the mid-Yuan Dynasty, and the temple is Yulan Society, with a common name of Pudu. Southland customs, Mid-Autumn Festival night, each family has its own vegetarian sacrifice, Luo is outside the door or squatting, wishing the dead and the injured wild ghosts. "